package org.sample.vm.oom;

import java.lang.reflect.Field;

import sun.misc.Unsafe;

/**
 * Direct memory out of memory.
 * 
 * VM Args: -Xmx20M -XX:MaxDirectMemorySize=10M
 */
@SuppressWarnings("restriction")
public class DirectMemoryOOM {

	private static final int _1MB = 1024 * 1024;
	
	public static void main(String[] args) throws Exception {
		Field unsafeField = Unsafe.class.getDeclaredFields()[0];
		unsafeField.setAccessible(true);
		Unsafe unsafe = (Unsafe) unsafeField.get(null);
		while (true) {
			unsafe.allocateMemory(_1MB);
			System.out.println("Allocate memory.");
		}
	}

}
